Jimmie Johnson has long prepared for Sunday – the day his record-setting streak of NASCAR championships likely ends.

Late in 2008, after winning his third straight championship to match Cale Yarborough’s once-seemingly-unmatchable record of three straight championships from 1976-78, Johnson asked, “How did Yarborough do in 1979?”

He chuckled. But he was half serious.

“This isn’t going to go on forever,” Johnson said back then during a visit to San Diego. “There are too many other good drivers out there. Too many things can happen. I want it to continue, but I know there will come a time when it’s over.”

It’s over.

Not officially.

There are still two races remaining in NASCAR’s Chase for the Championship playoff for the Sprint Cup title.

Even if he wins Sunday – and Johnson has four Phoenix wins with three of those leading to championships -- and leads the most laps, the most points Johnson can add to his total is 47.

Do the math. Johnson is done if either Edwards or Stewart finishes in front of him or rides his bumper to the checkered flag. And there are three other drivers standing between Johnson and the leaders.

“I am prepared for the streak to end,” Johnson said last weekend before losing more ground with a 14th-place finish at Texas. “I will be disappointed. I don’t want to see it end. But I always knew this day would come.

“We have to learn from this and move on.”

Johnson’s run of five straight titles has been one of the most dominating and controversial in NASCAR history.

His five straight titles came after NASCAR adopted the Chase for the Championship playoffs. The corps of “48 Haters” grew during Johnson’s run while the popularity of NASCAR waned – many detractors arguing that Johnson’s run was bad for the sport.

“Fans have been friendlier toward me this season,” Johnson said recently. “Maybe there’s an upside.”

But Johnson was never completely on his game this season. The driver won only one of 26 races during NASCAR’s regular season. Even his relationship with crew chief Chad Knaus seemed strained.

Johnson admitted he felt more stress this season.

“Weekends have been difficult this season,” Johnson said recently. “We used to go into a race and make a couple changes out of practice and be ready for the race. Then we’d be able to make more changes during the race.

“This season we’ve been chasing the changes. We haven’t been on top of our game. We have not finished off races like we needed to do to stay in contention. Sure there’s been frustration. We’ve been searching for answers that were there in the past.”

Johnson’s streak might be over, but the driver is not. He is only 36. There is no reason why he won’t rebound in 2012.

Only Richard Petty and Dale Earnhardt won more championships during their careers (eight apiece) than Johnson.